At the Eindhoven University of Technology, a hybrid vehicle is being developed that incorporates a conventional spark ignited engine as well as a high-speed glass-fibre flywheel. A steel belt CVT transports mechanical energy by means of ratio change from the flywheel to the wheels and vice versa during regenerative braking. The driveline has been designed for use in a compact passenger car in mixed city traffic and highway driving. In city driving, the medium sized hybrid passenger car requires only limited average power from its prime mover. The flywheel unit is employed to account for peaks in power demand and the IC engine can be operated in its region of best efficiency. However, in this working region, the engine generates an excess of power. Therefore, the engine is temporarily switched off whenever the flywheel contains sufficient energy. This way, the vehicle's fuel economy can be improved at low average loads. The resulting intermittent engine operation affects both fuel consumption and exhaust gas emission components. In order to quantify these instationary phenomena, experiments were conducted on a flywheel-clutch-engine test-rig. The definition of a standardised start-stop cycle, allowed for the evaluation of parameters that influence exhaust gas composition. High-speed NO, HC, and CO analysers were used to measure tailpipe emissions. The measurements revealed that start-stop operation of the single point injection engine in the hybrid driveline improved fuel consumption by more than 30 % over continuous operation in city driving. However, in this particular case of unchanged engine electronics, the improved fuel economy is penalised by a substantial increase of regulated exhaust gas emission. Although hot-restart dedicated engine electronics must be capable of lowering the engine-out NO emissions significantly, the potential for diminishing HC emission of a single point injection engine during intermittent operation is limited. Periodic engine operation also affects both upstream and downstream temperatures of the three-way catalyst, and therefore its conversion efficiency. To overcome this problem, the hybrid vehicle will be equipped with an active catalyst temperature control system.
Intermittent engine operation in a flywheel hybrid driveline
Diskontinuierlicher Motorbetrieb in einem Schwungrad-Hybridantrieb
1997
13 Seiten, 8 Bilder, 3 Tabellen, 14 Quellen
Aufsatz (Konferenz)
Englisch
Otto-Motor , diskontinuierliche Arbeitsweise , Hybridantrieb , Schwungrad , Glasfaser , Hochgeschwindigkeit , Niederlande , Stahlband , mechanische Energie , Fahrzeugrad , Bremsung , Pkw (Personenkraftwagen) , Stadtverkehr , Straßenfernverkehr , Leistung , Spitzenwert , Kraftstoffeinsparung , Abgasemission , Kohlenwasserstoff , Stickstoffmonoxid , Kohlenmonoxid , Messung , Nutzbremsung
Intermittent engine operation in a flywheel hybrid driveline
British Library Conference Proceedings | 1997
|Intermittent engine operation in a flywheel hybrid drive
Kraftfahrwesen | 1997
|A Management System for a Flywheel Hybrid Driveline
British Library Conference Proceedings | 1998
|A management system for a flywheel hybrid driveline
Tema Archiv | 1998
|Validation of a High Efficiency Flywheel Hybrid Driveline Concept
British Library Conference Proceedings | 1996
|